The present invention relates generally to formed-in-place concrete constructions, and more particularly, to a system which can be used to facilitate the construction of various types of structural elements using this technique.
One widely accepted technique which has been used to construct buildings or the like involves the use of reinforced concrete as the structural media. In general, this includes the construction of concrete forms in a desired shape, such concrete generally being reinforced by a metal framework contained within each form. By proper assembly of the forms, and by proper placement of the reinforcing framework, a variety of different constructions may be provided, such as flat slab, flat plate, one and two-way solid slab, one way joist and waffle flat plate constructions.
Irrespective of the construction desired in a particular application, the following technique is generally utilized to form such structures. First, a falsework is erected which serves as a support for the forms which are to be assembled to shape the structural element being formed. Such falseworks generally take the form of a scaffolding system or frame which is used to determine the general location of the structural element being formed. Wood joists and plywood decking, as indicated, are then placed over the scaffolding to form a temporary floor upon which the forms which will be used to shape the structural element will be assembled. After erection of the falsework, a measurement procedure is performed which marks out the location of the forms, often referred to as coffers, which will be used in the formation of the structural element. After the measurement procedure, the forms or coffers are then installed in position on the falsework and secured in place. Any perimeter barrier forms which are required are also installed at this time, resulting in the formation of a network of cavities capable of subsequently receiving poured concrete. After installation of the forms or coffers on the falsework, any metal reinforcing rods which are to be used in conjunction with the construction are installed within the concrete receiving cavities defined by the assembled forms or coffers. Also at this time, any small-gauge wires or pipes which may be required for a particular application are installed, so that they may become embedded in the concrete after it has been poured. After this assembly is completed, the concrete is poured into the concrete receiving cavities, and is allowed to surround the reinforcing rods or other structures which have been located within the concrete receiving cavities. The concrete is then allowed to cure in place. After curing, the falsework is removed from below the structural element which has been formed by removing the scaffolding, wood joists and plywood decking which previously served as a temporary support for the structural element.
After performing these steps, the structural element which has been formed must be finished to complete the building under construction. For example, it is often necessary to provide the building with plumbing lines and electrical conduit, to properly service the building. Additional wiring and fixtures must be provided for any lighting, fans, air conditioning, telephones, and the like, which are to be provided. Lastly, it is often necessary to provide some means for receiving a finished ceiling and/or non-load-bearing partitions beneath the structural element which has been formed, to enclose the building and prepare it for occupancy. Many times, special consideration must be given to unusually heavy components which which must be suspended from the ceiling, still further complicating matters.
To provide these functions, it is necessary to adapt the structural element which has been formed to receive the components previously described. Generally this is accomplished by attaching suitable anchors to the structural element, which anchors are capable of supporting the foregoing components in position as required. Often, this is accomplished using powder-actuated fasteners which are installed using a special tool or gun. To do so, blank shells loaded within the gun are used to inject nail-like anchors into the concrete. These anchors are then used to support components from the structural element. However, the special guns which are needed for this are expensive to purchase and are rather heavy, making their use difficult. Moreover, such devices are extremely dangerous and noisy in use. An alternative method of installation involves boring holes in the concrete element and, using appropriate reinforcements, bolting the component or component hanger directly to the structural element. Such a technique, while providing satisfactory results, is extremely labor intensive and time consuming. In addition to the labor costs involved, it is also necessary to provide equipment which is capable of boring the necessary holes in the structural element formed. This equipment is also expensive, particularly since the drill bits which are used in conjunction with such equipment have relatively short useful lives.
It may therefore be seen that a substantial amount of time and effort must be expended before finishing materials and components can be applied to a structural element which has been formed. It is therefore desirable to eliminate as many installation steps as is possible, resulting in attendant savings in time and labor costs.